<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style type="text/css">
			.small {
				width: 100px;
				height: 100px;
				background-color: #0000FF;
			}

			.big {
				width: 200px;
				height: 200px;
				background-color: red;
			}
		</style>
		<script src="common/js/jquery-3.4.1.js" type="text/javascript" charset="utf-8"></script>
		<script type="text/javascript">
			$(function() {
				$("#A").click(function() {
					//$("#A1").css({
					//	"width": "200px",
					//	"height": "200px",
					//	"background-color": "red"
					//});
					$("#A1").removeClass("small").addClass("big")
				})
			})
		</script>
	</head>
	<body>
		<button type="button" id="A">按钮</button>
		<div id="A1" class="small">

		</div>
	</body>
</html>
